The high prevalence of HIV/AIDS in Tanzania is a critical public health issue. Because heterosexual sex is the predominant route of transmission among this population, one way to prevent the spread of HIV is through the use of a male latex condom. Research has indicated that understanding the influence of alcohol use, gender, relationship power, and partner-type as part of a multifacted network of variables that predict condom use behavior is essential to developing targeted HIV prevention interventions that can effectively reduce the risk of new infections among high-risk populations, such as women in Tanzania. Currently, there is a complete absence of empirical research that addresses the different effects of these factors on men and women's ability to implement condom use, but a testable theory is available. The Theory of Gender and Power (TGP) will be used to generate causal hypotheses about the differential influence of alcohol use, perceived relationship power, and partner-type on men and women's self-reported difficulty implementing condom use. This project has two specific aims. The first is to conduct a formative study to create and validate experimental vignettes that can be used to provide reliable measures of perceived difficulty engaging in condom use under circumstances characterized by (a) the presence or absence of alcohol use, (b) a serious or a casual partner-type, and (c) a situation of low or equal power. The second specific aim is to conduct an experimental study using the previously described vignettes to test hypotheses generated from the TGP. Sexually active men and women from Northern Tanzania will respond to a series of vignettes that manipulate perceived relationship power, partner-type, and presence of alcohol use by indicating how "difficult" in would be to discuss, negotiate, and actually engage in condom use in each scenario. It is expected that women will report that it is most difficult to engage in condom use in situations characterized by the presence of alcohol use, a serious partner-type, and low power. Alternatively, for men, the only variable that will significantly affect difficulty implementing condom use is alcohol, such that it will be more difficult to implement condom use in a scenario where the man had been drinking. Relevance to Public Health: The results from this study will be used to further understanding of condom use behavior among a high-risk, underserved population in Northern Tanzania. This knowledge can be used to enhance the effectiveness of HIV prevention interventions and thereby reduce the incidence of HIV infection in the target population. Finally, this project can be used as a model for experimental work that improves the effectiveness of HIV prevention interventions of other populations in Sub-Saharan Africa.